庸よう愚ぐ

na-adjective, noun

mediocrity; imbecility; foolishness

Rare literary term for a state of being mediocre or foolish. In modern Japanese, 凡庸 or 愚かさ are more common.

• 彼かれの庸よう愚ぐな振ふる舞まいに皆みなが呆あきれた。